\subsection{Motivation}

Despite the rise of other wireless data transmission techniques, such as bluetooth or any methods based on electro-magnetic radio waves, infrared light is still widely being deployed, because of its simplicity and low cost. The subject of our project was consumer infrared (IR) transmission, with a special focus on common devices that can be found in nearly
every household, namley TVs and their remote controls. Those devices are common, cheap and insecure. With the growing number of Television devices connected to the Internet like the Samsung SMART TV\footnote{http://smart-tv.samsung.de/} or the LG Netcast\footnote{http://www.lg.com/us/netcast/index.jsp}, the latter becomes more and more important. Users may do their usual online activities using the TV. This includes the input of sensitive information, passwords etc. which should be kept secret.
In this work we try to investigate the threat scenario which follows the application of insecure infrared data transmission. This is in general limited to a narrow geographic location, but in any case unencrypted.

\begin{figure}[htp]
\centering
\includegraphics[width=0.6\textwidth]{img/samsung-tv}
\caption{A TV with internet connection and "Apps"}
\label{fig:samsung-tv}
\end{figure}

\subsection{Goals}

In the first place we wanted to find out typical distances and angles for common infrared systems used at home. Evaluating these forms a basis for estimations on the propagation of the infrared beams itself and the transported data.
Moreover, we try to manipulate data which is carried by infrared light. By taking our first results into account, we want to specify the number of places where a posible attacker could intercept the signal and introduce any threats. This includes an example implementation of a "firewall" (filter) for specific data packets carried by the light. For this purpose we wanted to utilise inexpensive and easy-to-use equipment, so we decided to use the Arduino as it is an open source platform, publicly available to everybody. This should prove not only the possibility of our attacks, but depicts the low barriers to apply them even for inexperienced people with a low budget.